申请人:EISAI CHEMICAL CO., LTD.
公开号:EP0675116A1
公开(公告)日:1995-10-04
Described is a protected aminothiazolylacetic acid derivative represented by the following formula (I):
wherein A represents a nitrogen atom or a methine group, R¹ and R² may be the same or different and individually represent a hydrogen atom, a lower alkyl group or a substituted or unsubstituted aryl group, R³ represents a lower alkoxy group, a halogenated lower alkoxy group, a triphenylmethoxy group, a lower alkyl group or an acyloxy group, and R⁴ represents a halogen atom, a hydroxy group, a lower alkoxy group or a substituted or unsubstituted amino group; and salts thereof; as well as processes for the preparation thereof. The protected aminothaizolylacetic acid derivative according to the present invention is an useful intermediate for introducing a 2-(2-aminothiazol-4-yl)-2-alkoxyiminoacetyl group or a 2-(2-aminotiazol-4-yl)-2-alkenoyl group into a cephem skeleton.
所描述的是一种受保护的氨基噻唑乙酸衍生物,由下式(I)表示:
其中,A 代表氮原子或甲基,R¹ 和 R² 可以相同或不同,且各自代表氢原子、低级烷基或取代或未取代的芳基,R³ 代表低级烷氧基、卤代低级烷氧基、三苯基甲氧基、低级烷基或酰氧基,R⁴ 代表卤原子、羟基、低级烷氧基或取代或未取代的氨基;及其盐类;以及其制备工艺。根据本发明的受保护氨基噻唑乙酸衍生物是一种有用的中间体,可将 2-(2-氨基噻唑-4-基)-2-烷氧基亚氨基乙酰基或 2-(2-氨基噻唑-4-基)-2-烯酰基引入头孢骨架中。